Systemd mount and swap units

These are the notes of a training course on systemd I gave as part of my work
with Truelite.

.mount and .swap units

Describe mount points similarly as what /etc/fstab, but with more
functionality and integration with the dependency system.

It is possible to define, for example, a filesystem that should be mounted only
when the network is available and a given service has successfully started, and
a service that should be started only after a given filesystem has been
successfully mounted.

At boot, systemd uses systemd-fstab-generator
to generate mount and swap units from /etc/fstab, so that the usual fstab
configuration file can still be used to configure the file system layout.